BeWelcome - Open your door to the world!
Skyscanner - Skyscanner.com compares over 1000 airlines to find you the cheapest airfares, fast.
Hospitality Club - Free network of people around the world who offer free accommodation, advice and help when they are traveling - hospitality exchange. Free membership.
KAYAK - KAYAK is a travel search engine that searches hundreds of other travel sites at once. Our helpful tools & features find you the information you need to make the right decisions on flights, hotels, rental cars and vacation packages.
Trustroots - Travellers community for sharing, hosting and getting people together.
Momondo - Find cheap flights with Momondo.